Re: Adds redirect-lilypond-output option to lilypond-book (issue4664060)

[Phil Holmes]

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Sent: Sunday, July 03, 2011 7:25 PM
Subject: Re: Adds redirect-lilypond-output option to lilypond-book 
(issue4664060)


> LGTM, and fantastic website with testing info.
>
>
> I have three requests for future work, but this patch should get pushed
> first.
>
> - the final "Child returned 1" doesn't tell me (as a user/doc-writer,
> rather than phd student) anything.  How hard would it be to put the
> "Look in logfile..." line after that one?
> (a very quick skim suggests that this would be icky, so maybe forget
> about it)
> Or maybe just make the "child returned" into "Error: could not complete
> command", or maybe "Error: child returned
> __insert_error_code_interpretation__" ?

AFAICS this is a doddle to change.  I'll do this as a follow up piece of 
work unless you want it earlier.

> - it's a bit weird to see tons of output even when using the
> --redirect-lilypond-output.  Would it be possible to make a
>   --use-logfiles
> option which automatically turns on --redirect-lilypond-output, but also
> captures stderr+stdlog and writes *those* to a file?
> (and maybe in addition to writing the log file, it would display the
> "Error: child returned __blah_blah__" line)

Don't think so, at present.  From my reading of the Python, progress and 
error messages mostly go to stderr, as does the error message.  To make it 
so that we don't see progress but do see the error message would be 
something of a rewrite of how progress and errors are handled in lilylib and 
lilypond-book.  So, we need the GOP debate on stderr versus stdout.

> - it would be great to automatically show the last X lines of the
> logfile.  (but that's definitely something to do later on)

It needs to be a bit cleverer than that.  The last 5 lines are:

Converting to `/home/phil/TestFolder/BookTest/c4/lily-4139797f-2.pdf'...
Writing /home/phil/TestFolder/BookTest/c4/lily-4139797f-systems.texi...
Writing /home/phil/TestFolder/BookTest/c4/lily-4139797f-systems.tex...
Writing /home/phil/TestFolder/BookTest/c4/lily-4139797f-systems.count...
error: failed files: "c4/lily-4139797f.ly"

In this case, it needs line 32 out of 52.... (which says):

rest-note-collision.ly:9:0: error: unknown escaped string: `\PhilWasHere'

I'll have a think.

--
Phil Holmes